Graphics processing systems are known that break down a display screen into subsections and then render each subsection separately. Where graphic systems employ both a host processor and graphics processor, because the software driver or other application is executing on the host processor, the host processor tends to keep track of which portion of the screen it wants rendered. However, if the host processor needs to rearrange its command list and send only those commands dealing with a currently rendered screen subsection, this can require additional sorting and command jumping that must be carried out by the host processor. This can result in performance degradation and require additional overhead for the host processor.
Another solution may be to render all vertice information for all objects to be rendered for the entire screen and then throw out or discard the fully rendered objects that are not necessary for a given screen subsection. However, such an approach wastes valuable graphics processor resources by requiring all the objects to be rendered and throwing away the objects that are not needed for that particular portion of the screen that is being rendered.